Bariatric device and method

ABSTRACT

A bariatric device and method of causing at least partial satiety includes a body having a wall defining a lumen. The wall is configured to generally conform to the shape and size of i) the abdominal portion of the esophagus and/or ii) the proximal cardiac portion of the stomach. The wall is adapted to exert a force on the i) abdominal portion of the esophagus and/or ii) the proximal cardiac portion of the stomach thereby influencing a neurohormonal feedback mechanism to cause at least partial satiety by augmenting fullness caused by food and simulating fullness in the absence of food. A fixation system is included to resist distal migration of the body. The fixation system includes at least a portion of the wall having a tissue ingrowth characteristic to promote ingrowth of tissue in the wall.

CROSS REFERENCE TO RELATED APPLICATIONS

The present invention is a continuation of U.S. patent application Ser.No. 12/915,952, filed on Oct. 29, 2010, which is a continuation of U.S.patent application Ser. No. 11/463,192, filed on Aug. 8, 2006, now U.S.Pat. No. 7,846,174, which is continuation-in-part application ofInternational Application No. PCT/US2005/036991, filed on Oct. 13, 2005,entitled BARIATRIC DEVICE AND METHOD, which claims the benefit of60/619,308 filed on Oct. 15, 2004; and claims the benefit of 60/632,147filed on Dec. 1, 2004; and claims the benefit of 60/636,845 filed onDec. 15, 2004; and claims the benefit of 60/711,310 filed on Aug. 25,2005, the disclosures of which are incorporated herein in theirentirety.

BACKGROUND OF THE INVENTION

The present invention is directed to a bariatric device and method ofcausing at least partial satiety in a patient. In particular, thepresent invention is directed to a bariatric device and a method ofcausing at least partial satiety in a patient by a noninvasive orminimally invasive technique.

Obesity is a large and increasing problem in the United States andworldwide. In round numbers, from the period encompassing the year 1990to the period encompassing the year 2000, the prevalence of overweightpeople (BMI greater than 25) increased from 56 percent of United Statesadults to 65 percent and the prevalence of obese adults (BMI greaterthan 30) increased from 23 percent to 30 percent. Likewise, theprevalence of overweight children and adolescents (ages 6-19 years)increased from 11 percent in the period encompassing the year 1990 to 16percent in the period encompassing the year 2000. The increasingprevalence of overweight among children and adolescents will make theproblem even greater when they reach adulthood. The problem is notlimited to the United States. Between 10 percent and 20 percent ofEuropean men are obese and between 10 percent and 25 percent of Europeanwomen are obese. Numerous medical conditions are made worse by obesityincluding Type II diabetes, stroke, gallbladder disease and variousforms of cancer. Approximately 500,000 people in North America andWestern Europe are estimated to die from obesity-related diseases everyyear and obesity is estimated to affect more than one billion adultsworldwide. Therefore, there is a pressing and unmet need for a solutionto the epidemic problem.

Various techniques are known for reducing obesity in patients. Knowntechniques tend to be based upon restricting food movement and/ornutrient absorption. One example is gastric bypass surgery on thepatient, which is highly invasive. The goal of such surgery is to form apouch from a portion of the stomach to reduce the volume of the space inthe stomach receiving food. When the patient ingests food, the pouch isfilled which stretches the stomach wall and produces satiety. Onedifficulty with such procedure is that it requires food to fill thepouch to create satiety. As a result, dietary restrictions are requiredfor effective operation of the pouch. Such restrictions includewithholding of liquids during meals to avoid washing the food from thepouch. Also, liquids with substantial calories tend to pass through thepouch without creating substantial satiety. Moreover, the opening fromthe pouch tends to become enlarged over time, thus allowing more food topass while achieving reduced satiety. Thus, patients undergoing suchsurgical techniques often experience gradual weight gain over time.

Alternative weight loss devices and methods have been proposed. However,such devices and methods may be difficult to place in the patient, havequestionable efficacy, and may cause undesirable side effects.

SUMMARY OF THE INVENTION

The present invention utilizes a new principle of implied satiation. Thepresent invention provides a bariatric device and method of causingsatiety in a patient that augments the natural response of the body.This may be accomplished using a non-invasive or minimally invasiveprocedure with a device that may be removable or absorbable. Moreover,satiety may be caused in a manner that does not interfere with otherbody functions, such as operation of normal reflux mechanism, bileducts, taking of medications, and the like. The implied satiationtechnique of the present invention does not rely on either therestrictive or malabsorptive techniques of the prior art.

A bariatric device, according to an aspect of the invention, includes abody having a wall defining a lumen. The wall is configured to generallyconform to the shape and size of i) the abdominal portion of theesophagus and/or ii) the proximal cardiac portion of the stomach. Thewall is adapted to exert a force on the i) the abdominal portion of theesophagus and/or ii) the proximal cardiac portion of the stomach therebyinfluencing a neurohormonal feedback mechanism to cause at least partialsatiety by augmenting fullness caused by food and simulating fullness inthe absence of food. A fixation system is included to resist distalmigration of the body. The fixation system includes at least a portionof the wall being adapted to promote ingrowth of tissue in the wall.

The fixation system may include at least one opening in the wall topromote ingrowth of tissue. The at least one opening may be a pluralityof discrete openings. The at least one opening may be a lattice ofopenings. The at least one portion of the wall may be substantially theentire wall or a limited portion of the wall.

The fixation system may include another fixation mechanism to resistdistal migration of the body. The body may be made at least in part froman absorbable material. The lumen may be substantially free ofrestriction. The wall may be adapted to exert a force without thepresence of food.

A bariatric device, according to another aspect of the invention,includes a body having a wall defining a lumen. The wall includes a wallportion defining an esophageal member sized to conform to an abdominalportion of the esophagus, another wall portion defining a cardiac membersized to conform to a proximal cardiac portion of the stomach and afurther wall portion extending between the esophageal member and thecardiac member. The esophageal member and the cardiac member are adaptedto exert a force on the abdominal portion of the esophagus and theproximal cardiac portion of the stomach thereby influencing aneurohormonal feedback mechanism to cause at least partial satiety byaugmenting fullness caused by food and simulating fullness in theabsence of food. At least a portion of the wall is adapted to promotetissue ingrowth. In this manner, ingrowth of tissue in the portion ofthe wall in reaction to presence of the body in the recipient fixes thebody to the anatomy of the recipient to resist distal migration.

The portion of the wall may include at least one opening in the wall.The at least one opening may be a plurality of discrete openings. The atleast one opening may be a lattice of openings. The at least one portionof the wall may be substantially the entire wall or a limited portion ofthe wall.

Another fixation mechanism may be included to resist distal migration ofthe body. The body may be made at least in part from an absorbablematerial. The lumen may be substantially free of restriction. The wallmay be adapted to exert a force without the presence of food.

A method of causing at least partial satiety, according to yet anotheraspect of the invention, includes positioning a body at i) an abdominalportion of the esophagus and/or ii) a proximal cardiac portion of thestomach. The body has a wall defining a lumen. The wall is configured togenerally conform to the shape and size of i) the abdominal portion ofthe esophagus and/or ii) the proximal cardiac portion of the stomach. Aforce is exerted with the wall at i) the abdominal portion of theesophagus and/or (ii) the proximal cardiac portion of the stomachthereby influencing a neurohormonal feedback mechanism of the patient tocause at least partial satiety by augmenting fullness caused by food andsimulating fullness in the absence of food. The body is fixed againstdistal migration including promoting ingrowth of tissue at a portion ofthe wall.

The portion of the wall may include at least one opening in the wall.The at least one opening may be a plurality of discrete openings. The atleast one opening may be a lattice of openings. The portion of the wallmay be substantially the entire wall or a limited portion of the wall.

The body may be further fixed with another fixation mechanism to resistdistal migration of the body. The ingrowth of tissue may promotepermanence of the body in the anatomy of the recipient. The ingrowth oftissue may incorporate the body in the anatomy of the recipient. Theingrowth of tissue may resist infection. The body may be removed fromthe recipient by removal of the ingrowth of tissue.

Thus, it can be seen that embodiments of the present invention providean implied satietor and implied satiation method that does not requirefood to generate the satiety through the neurohormonal mechanism of thebody. This advantageously produces at least partial satiety in thepatient in the absence of food, as well as augmenting fullness caused byfood during the ingestion of the food. Moreover, because satiety is notcaused by food, the patient would not necessarily need to be subject todietary restrictions, such as withholding of liquids during meals orwithholding of liquids having substantial calories.

Moreover, in contrast to surgical procedures, embodiments of the presentinvention provide a bariatric device and method of causing at leastpartial satiety that is minimally invasive and which avoids many of thepotential side effects of gastric bypass surgery and other surgicalprocedures, such as adjustable gastric banding, and the like. Also,because of the placement of the device, there is no interference withoperation of gastric functions, such as with the bile ducts, and thelike. Further, as previously noted, the bariatric device can be adaptedto allow the gastro-esophageal junction to function normally without anysignificant interference or impediment. Also, embodiments of theinvention provide a bariatric device and method of inducing at leastpartial satiety in the patient that does not operate on the basis ofcausing flu-like symptoms in the patient in a thwarted effort to attemptto induce the patient to eat less, such as may occur by the placement ofdevices in the patient's duodenum, or the like.

Additionally, in contrast to pouches formed in gastric bypass surgery,embodiments of the present invention do not include a discharge openingthat is subject to enlargement with the passage of time, therebyeliminating at least one source of gradual weight gain in patientsundergoing gastric bypass surgery.

Moreover, because it is a non-invasive or minimally invasive procedure,embodiments of the present invention may be applied not only to morbidlyobese patients, but also to obese patients, overweight patients,adolescents, and potentially even children.

Thus, it is seen that the present invention is embodied in a bariatricdevice and method including a body having an expandable wall, whichevokes normal neurohormonal responses associated with fullness orsatiety. The body wall does so by acting on one or more portions of thedistal esophagus and/or the cardia of the patient. The normal fillingsensation of the stomach is augmented and amplified. Further, it hasbeen found that the body appears to have a “satiety continuum” where aperson transitions from hungry, which is on one end of the continuum orspectrum where there is a lack of satiety, to lacking hunger or beingsatisfied after eating and to being full with continued consumption. Ifthe person continues to eat to the point of overeating, the person thenbecomes nauseous, which represents the other end of the continuum. Asthe pressure applied to the distal esophagus and/or the cardia of apatient is increased, the further along the patient will be on this“continuum” or spectrum. Ideally, then for an extremely overweightperson, the bariatric device of the present invention may be best usedif sufficient pressure is applied so that the patient is on the nauseaend of the spectrum or just below at a “sub-nausea” point.

These and other objects, advantages and features of this invention willbecome apparent upon review of the following specification inconjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of a bariatric device positioned at the abdominalportion of the esophagus, the esophageal-gastric junction and theproximal cardiac portion of the stomach of the patient;

FIG. 2 is a perspective view of an alternative embodiment of thebariatric device in FIG. 1;

FIG. 3 is a bottom plan view of the bariatric device in FIG. 2;

FIG. 4 is the same view as FIG. 2 of another alternative embodiment;

FIG. 5 is the same view as FIG. 4 illustrating an alternative controltechnique;

FIG. 6 is the same view as FIG. 2 of yet another alternative embodiment;

FIG. 7 is the same view as FIG. 6 illustrating adjustment ofrestriction;

FIG. 8 is the same view as FIG. 2 of yet another alternative embodiment;

FIG. 9 is the same view as FIG. 2 of yet another alternative embodiment;

FIG. 10 is the same view as FIG. 1 of yet another alternativeembodiment;

FIG. 11 is the same view as FIG. 1 of yet another alternativeembodiment;

FIG. 12 is the same view as FIG. 2 of yet another alternativeembodiment;

FIG. 13 is the same view as FIG. 2 of yet another alternativeembodiment;

FIG. 14 is the same view as FIG. 2 of yet another alternativeembodiment;

FIG. 14A is a perspective view of an alternate embodiment of thebariatric device of FIG. 1; and

FIG. 15 is a block diagram of a technique for selecting the level ofpressure exerted by the body wall.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now specifically to the drawings, and the illustrativeembodiments depicted therein, a bariatric device, or implied satietor,15, which causes satiety by acting on the abdominal portion of theesophagus, and/or the esophageal-gastric junction and/or the proximalcardiac portion of the stomach, is illustrated in FIG. 1 beingpositioned in the patient. Device 15 includes a body 16 having anexpandable wall 17 thereby defining a transverse passage, or lumen 18through the body. Body 16 is designed to conform to the shape and sizeof the abdominal portion of the esophagus, the esophageal-gastricjunction and/or the proximal cardiac portion, or cardia, of thepatient's stomach. The present invention is embodied in variousbariatric devices. The devices may be removable, absorbable and/orpermanent. The devices may be manufactured from a synthetic or abioprosthetic material. While the invention is illustrated with a meshwall, other configurations are possible, such as coil configurations,and the like. Bariatric device 15 may be positioned utilizing varioustechniques, such as endoscopic placement with fluoroscopic assist.

Wall 17 is configured to exert an outward pressure, typically agenerally radial outward pressure, at the abdominal portion of theesophagus, the esophageal-gastric junction and/or the cardia of thepatient. This may be accomplished, for example, by configuring the wallto have a proximal portion 17 a to create an interference fit with theabdominal portion of the esophagus and/or a central portion 17 bconfigured to create an interference fit with the esophageal-gastricjunction and/or a distal portion 17 c configured to create aninterference fit with the patient's cardia. The pressure exerted by wallportions 17 a, 17 b and/or 17 c influences the neurohormonal feedbackmechanism present at the esophagus and/or stomach to cause at leastpartial satiety. As will be discussed in more detail below, the pressureexerted by the extendable wall may be fixed or adjustable. The forcethat influences the neurohormonal feedback mechanism present at theabdominal portion of the esophagus, the esophageal-gastric junctionand/or the cardiac portion of the stomach is intended to be relativelyconsistent over as large an area as reasonably possible. The forceexerted by the wall of the bariatric device is believed to activatestretch receptors located in the abdominal portion of the esophagus, theesophageal junction and/or the cardia. In contrast to prior proposeddevices, which require that the patient ingest food in order toinfluence neurohormonal feedback mechanisms, bariatric device 15simulates fullness in the absence of food. It also augments fullnesscaused by food.

This interference fit may be created by a self-extendable, orself-expanding, wall. Alternatively, it may be created by an extendablewall, such as a balloon-extendable wall. The extended wall diameter ischosen so that it is somewhat oversized compared to the diameter of theconduit in which it is positioned, namely, the abdominal portion of theesophagus, the esophageal-gastric junction and/or the cardia. Aself-extendable wall may be, by way of example, formed from a material,such as metal, fibers or fibrous materials, including carbon fibers, andmay be a wall made from a self-extendable silicone-coated material. Forexample, the wall may be formed from a metal sheet, such as a Nitinolsheet, formed for example, by laser cutting, or from a coil or latticestructure formed from a metal or carbon fiber, which may be encapsulatedor embedded in an insert polymer, such as silicone or the like.Alternatively, the wall may be extended by a balloon or fluid extendablereservoir expanding the wall outwardly, including generally radiallyoutwardly, to a position firmly against the wall of the conduit in whichthe body is inserted. This inflation may be accomplished endoscopicallywith a blunt needle or with a control as will be discussed in moredetail below.

As can be seen in FIG. 1, wall 17 is longitudinally non-symmetrical withrespect to the central longitudinal axis “L” defined by the direction ofmovement of the food along the patient's esophagus and stomach. Inparticular, as one moves along axis L, the cross-sectional configurationof wall 17 varies proximally to distally. For example, wall portions 17a and 17 b are generally cylindrical in shape and wall portion 17 c isfrusto-conical in shape, flaring outwardly from a distal end of wallportion 17 b. Wall portion 17 c is angled to conform to the cardiacnotch. Wall 17 may also be radially non-symmetrical with respect to thislongitudinal axis “L”. In particular, certain portions of wall 17 are ata greater radial distance from axis L than portions of the wall at adifferent location around axis L. For example, wall portion 17 c isenlarged at 19 to extend to more of the fundus of the cardia, such asthe angle of His. This enlarged portion 19 makes wall 17 radiallynonsymmetrical with respect to axis “L”.

The narrow portion of lumen 18, which generally is the portion in thepatient's esophagus, may have a length that is no longer required toprovide enough force to produce satiety. In the illustrative embodiment,the narrow portion of lumen 18 is less than 9 cm in length. In certainembodiments, the narrow portion of lumen 18 is in the range of between 6cm and 7 cm in length. This reduces the tendency of food to get caughtin the lumen as well as any interference with peristalsis of theesophagus while producing force over a sufficient surface area toproduce satiety.

In the embodiment illustrated in FIG. 1, bariatric device 15, andcorresponding method of causing satiety in a patient, includes providingat least a portion 20 of middle wall portion 17 b that does not exert asubstantial pressure or force. Such portion may be made from a flaccidmaterial, such as a non-self-expandable material, or may be formed froma plurality of discrete wall portions that simply connect the proximalportion 17 a to the distal portion 17 c, as more fully described inreference to FIG. 14A below. These discrete wall portions may beinterconnected to form a mesh or may be unconnected from each other tosimply act as connectors between the proximal portion 17 a and thedistal portion 17 c. The device would be positioned such that thenon-self expanding portion 20 covers the gastro-esophageal sphincter.This would allow the anti-reflux mechanism of the gastro-esophagealjunction to operate generally normally because the wall of portion 20would not exert any significant pressure on the sphincter. Thisembodiment allows the patient to belch, vomit, and the like, whileresisting reflux. In bariatric device 15, proximal wall portion 17 a isself-expandable and is generally cylindrical in shape to conform to theshape and size of the abdominal portion of the esophagus and distal wallportion 17 c is self-expandable and is generally frusto-conically inshape to conform to the shape and size of the proximal cardiac portionof the stomach.

Bariatric device 15 may include a fixation system 21, which is capableof resisting distal migration of the device. Fixation system 21 mayinclude a series of anchors 22 illustrated as a series of V-shapeddownwardly directed appendages from wall 17. Alternatively, the anchorsmay be in the shape of downwardly directed barbs or hooks, metallicanchors extending radially from said body, or the like. Such arrangementprovides fixation against migration, typically distal migration, whileallowing the device to be easily removed from the patient because theanchors may be configured to provide less resistance to proximalmovement. In the embodiment illustrated in FIG. 1, the anchors arepositioned at or near the esophageal-gastric junction, such asproximally at distal portion 17 c of the wall. This positioning of theanchor takes advantage of the fact that the esophageal gastric junctionis thicker and, therefore, stronger at this location.

A bariatric device 115 includes a wall 117 having a proximal wallportion 117 a that applies outward pressure, such as generally radiallyoutward pressure, to the abdominal portion of the esophagus, a distalportion 117 c that applies outward pressure, such as generally radiallyoutward pressure, to the proximal cardiac portion of the stomach, and amiddle portion 117 b that is positioned at the esophageal-gastricjunction (FIG. 2). As with bariatric device 15, in bariatric device 115the central portion 117 b is made from a non-expandable material, suchas a flaccid material 120. Also, distal portion 117 c includes anenlarged portion 119 that extends to more of the function of the cardia,such as the angle of His. Flaccid material 120 includes openings 123that allow ingrowth of material. Openings 123 define at least in part afixation system 121. Fixation system 121 may include a secondary, ortemporary, means for anchoring bariatric device 115 while allowingtissue to ingrowth through openings 123. Such secondary fixation systemmay include stitches, staples, or the like. Openings 123 may be sizedappropriately to accept such stitches or staples. The sutures could bedissolvable or non-dissolvable. Openings 123 may be as few as, forexample, five openings in the flaccid material portion 120.Alternatively, they may be a lattice of small holes that allow tissueingrowth. The use of tissue ingrowth utilizes the body's reaction to thebariatric device 115 in order to assist in fixing the device againstdistal migration. Further, the tissue ingrowth, which results from themucosa essentially incorporating the device into the anatomy of thepatient, provides resistance to infection. This ingrowth can be in aportion of the device body or through the entire device body. While someirritation of the mucosa may occur when bariatric device 115 is removed,any such irritation should be relatively minor and readily healed. Aswith all fixation systems described herein, fixation system 121 may beused in combination with other fixation systems, such as fixation system21, or the like. Alternately, the tissue ingrowth may be used to promotepermanence—in other words to incorporate the device into the body of thepatient.

An alternative bariatric device 215 includes a body 216 having anexpandable wall 217 (FIGS. 4 and 5). Expandable wall 217 defines aninternal chamber 24 throughout at least a portion of the proximalportion 217 a, middle portion 217 b and distal portion 217 c of wall217. Chamber 24 may be a single unitary chamber that extends the lengthof wall 217 or may be a series of separate chambers that are eitherinterconnected or separated from each other. For example, a chamber maybe positioned around proximal portion 217 a of wall 217 that is sizedand shaped to be positioned at the patient's abdominal esophagus and achamber may be positioned at distal portion 217 c that is sized andshaped to be positioned at the patient's cardia while no chamber ispresent at all or a portion of 217 b that is configured in size to be atthe esophageal-gastric junction of the patient. In this manner, wall 217would not be substantially expandable at the gastro-esophagealsphincter, thereby reducing interference with normal operation of suchsphincter, as previously discussed.

As can be seen in FIG. 4, a port 25 may be provided to chamber 24 inorder to allow access by a needle 26 connected with a device 27 that isendoscopically inserted in the patient and used to either add fluid toor remove fluid from chamber 24. In this manner, the amount of forceexerted by wall 217 may be varied or adjusted. In this manner, forexample, a greater amount of force may be applied to a morbidly obesepatient, such as one that is more than 40 pounds overweight, while alower amount of pressure may be applied to patients that are overweightor mildly obese, such as those that are 30 to 40 pounds overweight, forexample. Bariatric device 25 is illustrated with a fixation system inthe form of anchors 22, although other fixation systems previouslydescribed may be utilized. Additionally, distal portion 217 c may beradially symmetrical with respect to the longitudinal axis “L” of thedevice or may be non-symmetrical by including the enlarged portion ofdistal wall portion 217 c as previously described.

As illustrated in FIG. 5, reservoir 24 of bariatric device 215 may,alternatively, be connected with a fluid reservoir 28 positioned withinthe patient and including a control 29 that is configured to selectivelytransfer between fluid reservoir 24 in the bariatric device and fluidreservoir 28 in the patient. In this manner, control 29 may control theamount of fluid in fluid chamber 24, thereby adjusting the amount offorce exerted by the wall 217 of the device on the conduit in which itis positioned. An optional patient operable control 31 may be providedand interconnected with internal control 29, such as by aradio-frequency link 32, in order to allow a patient or medicalattendant to modify the amount of pressure exerted by wall 217.

Control 29 may provide for a temporal adjustment of the amount ofpressure exerted by bariatric device 215 on the patient's distalesophagus and/or proximal stomach. By way of example, control 29 mayinclude an algorithm that causes fluid to be transferred from fluidreservoir 30 to fluid chamber 24 of the device 215 in order to increasethe amount of pressure, typically radial pressure, exerted by wall 217during general waking hours of the patient when satiety is desired.Control 29 can further be programmed to transfer fluid from reservoir 24to reservoir 30 during periods of time when the patient is expected tobe sleeping and satiety is not required. Patient control 31 may,alternatively, allow manual adjustment of the amount of force exerted bywall 214 of device 215. For example, when the patient retires at night,the patient may operate user control 31 in order to instruct control 29to transfer fluid from chamber 24 to fluid reservoir 30, therebyreducing pressure exerted by wall 217. When the patient awakes, thepatient may then utilize user control 31 in order to cause control 29 toincrease the amount of pressure exerted by wall 217. This temporalcontrol of the amount of force exerted by wall 217 should overcome anypotential tachy phylaxis that may result in the diminishing response ofthe neurohormonal system of the patient to the force exerted by wall217. Alternatively, the temporal control may be utilized, whereappropriate, to adjust the amount of pressure with respect to eatingtimes of the patient, or the like. Control 29 may, alternatively,monitor certain hormonal levels of the patient in order to determinewhen the patient is expected to eat a meal and may even be aself-learning control system in order to learn the variations in thepatient's hormonal levels.

An alternative bariatric device 315 may further include a restrictioncomponent 33 restricting discharge of food from lumen 18 (FIG. 6).Restriction component 33 may be in the form of a chamber 34 extendingwithin the lumen of body 316. In the illustrative embodiment,restriction component 33 is adjacent to distal portion 317 c of wall317, but could be at other locations along wall 317. Chamber 34 may beincreased or decreased in volume utilizing various techniques, such asby adding or withdrawing a fluid, such as a gas or a liquid, via a bluntneedle 26 (FIG. 7). Other known devices, such as an external electronicdevice that communicates with a control (not shown) and a pump/fluidreservoir within the patient, may be used to adjust the size ofrestriction component 33. With such configuration, the external controlmay actuate the pump through the internal control in order to increaseor decrease the size of chamber 24. Alternatively, the internal controlmay be programmed to carry out the adjustment. Chamber 28 restricts thecross-section of lumen 18. Such restriction resists egress from lumen 18of walls 16 and thereby resists the continued ingestion of food pastdevice 315. This may be useful in patients who tend to continue to eatpast satiety.

FIG. 8 illustrates an alternative bariatric device 415 having a body 416with a restriction component 133 in the form of an inflatable reservoiror chamber 134, which surrounds the distal portion 418 a of the lumen418. Reservoir 134 provides an adjustable restriction wherein, asadditional fluid is added to chamber 134, the increase in the volume ofthe chamber restricts the diameter of lumen 418 thereby adjusting theability to resist egress from the lumen of bariatric device 415 therebyproviding a variable restriction to ingestion of food. Chamber 134 mayalso be capable of increasing the external diameter of the device wall417 c thereby placing additional pressure on stretch receptors at thecardia of the patient's stomach.

An alternative bariatric device 515 may include a body 516 having a wall517 including an anti-reflux component 35 (FIG. 9). Anti-refluxcomponent 35 may be in the form of a one-way valve in order to resistreflux from the stomach to the esophagus. As best seen in FIG. 9,anti-reflux component 35 may be in the form of a tubular extension oflumen 518 that expands to allow distal movement of food but collapses toreduce reflux.

An alternative bariatric device 615 includes a body 616 having a wall617 that is self-expandable at a proximal portion 617 a, a middleportion 617 b and a distal portion 617 c, the latter being configured tothe cardiac notch of the patient (FIG. 10). Bariatric device 615includes a fixation system 21, such as a series of anchors 22, at theesophageal-gastric junction of the patient. The entire surface of wall617 is made of a self-expanding material.

An alternative bariatric device 715 illustrated in FIG. 11 has a body716 in which egress from the lumen 718 is from a discharge portion 40 ofthe device located at or near the patient's intestines. This providesadditional weight loss by substantially bypassing the patient's stomachand discharging to the intestines. Device 715 may include a series ofperforations 36 at discharge portion 40 in order to distribute theegress from lumen 718 along the small intestine of the patient. Use ofbariatric device 715 may require dietary restrictions to avoid foodcollection in the elongated lumen.

Anchors may be positioned at various locations along the exterior of thewall of the device. For an example, an alternative bariatric device 815is illustrated in FIG. 12 with a body 816 having a wall 817 havinganchors, such as V-shaped appendages, barbs, or hooks distributed alongthe outer wall of the body. The fixation system may also be in the formof a balloon-expandable wall 817 c defining a chamber 37 that appliessufficient pressure on the conduit in which the device is located inorder to resist distal migration of the device. The balloon can extendthe device wall to produce fixation and can be deflated in order toallow the device to be removed. FIG. 13 illustrates an alternativebariatric device 815′ having a body 816 with a wall 817 defining a lumen818 without a chamber. Other fixation systems may be apparent to theskilled artisan, such as stitching, stapling, and the like.

An alternative bariatric device 915 illustrated in FIG. 14 includes abody 916 having a wall 917 that is positioned virtually entirely withinthe patient's stomach. Wall 917 is of a size and shape to conform to thecardiac portion of the stomach, cardia, and is configured to exertpressure, typically radial pressure, on the cardia. Device 915 includesa fixation system 922 that engages the cardia or the esophageal-gastricjunction.

As noted above, the non-self-expanding portion of bariatric device ofthe present invention may be formed from discrete wall portions.Referring to FIG. 14A, device 1015 is of similar construction to device15 and includes a body 1016 having an expandable wall 1017, whichdefines a lumen 1018. Wall 1017 is similar to wall 17 and includes aproximal portion 1017 a to exert pressure on the abdominal portion ofthe esophagus and a distal portion 1017 c that is configured to exertpressure on the cardia. For further details of portions 1017 a and 1017c reference is made to the previous embodiments.

In the illustrated embodiment, the central portion 1017 b of the body1016 is formed from discrete wall portions 1020, which connect theproximal and distal portions 1017 a, 1017 c of wall 1017 together. Wallportions 1020 may act as tension members between the distal portion andthe proximal portion and may further act as compression members tomaintain the distal and proximal portions at a desired spacing, butwhich do not exert any significant outward or radial pressure on thegastro-esophageal junction. Wall portions 1020 may be generally equal insize and evenly spaced around the perimeter of body 1016 or may beunevenly spaced and, further, may have different widths and lengths. Forexample, the lengths of the wall portions may fall in a range of 0.75 cmto 1.5 cm. The number of wall portions may vary, with the illustratedembodiment depicting four wall portions that are generally evenly spacedaround the perimeter of body 1016.

As noted above, wall portions 1020 optionally form a non-self-expandingportion of wall 1017 and align with the gastro-esophageal junction toallow the junction to function normally. The spaces between the wallportions 1020 may comprise holes or openings or may be filled by aflexible membrane or flaccid material.

In addition, wall portions 1020 may provide fixation points, forexample, for sutures to secure device 1015 at or near thegastro-esophageal junction in which case the material forming wallportions 1020 may formed from a relatively stiff material, such asfibers or fibrous material, for example, embedded in silicone, forexample.

Further, the upper open end or entrance of body 1016 may be flaredoutwardly to bear or seal against the esophageal wall to essentiallyclose off the space or gap between device 1015 and the esophagus.

Various delivery systems may be utilized to deliver any of the bariatricdevices 15-1015 to the patient. Such a delivery system may include atube device (not shown) into which the bariatric device is compressed.The tube device may be a stiff or flexible tube and be sized and shapedto easily fit within the patient's esophagus. Such a delivery systemincludes a deployment mechanism (not shown) to retract the bariatricdevice from the tube. As the bariatric device is removed from the tube,it assumes its expanded form. If a self-expanding wall is utilized, thebariatric device will assert pressure, such as a generally radialpressure, on the distal esophagus and/or the cardia of the patient whenremoved from the tube. If an expandable wall is utilized, such as abladder, the bladder is inflated in order to exert pressure. Variousmarkers, such as fluorescent markers, may be applied to the wall of thebariatric device in order to allow for fluoroscopic assist in theplacement of the device.

A method 50 may be provided for monitoring and, if desired, adjustingthe amount of satiety produced by the bariatric device and method (FIG.15). In method 50, a bariatric device 15-1015 is inserted in the patientat 52 and a level of pressure, such as generally radial pressure, isapplied by the body wall of the device. The level of satiety ismonitored, such as by monitoring the patient's hypothalamus at 54, suchas with a Positron Emission Tomography (P.E.T.) scan. The P.E.T. scanproduces a visual image of the hypothalamus that changes colors with theamount of activity of the hypothalamus. By observing the color of thehypothalamus through the P.E.T. scan, a determination is made at 56whether an appropriate level of satiety is obtained. If it is, then theprocedure is done at 58.

If it is determined at 56 that an appropriate level of satiety is notbeing obtained, the process returns to 52 where a different level ofpressure may be adjusted by the body. The adjustment of pressure may bein the form of adding or subtracting fluid from a bariatric devicehaving an expandable wall by the use of a chamber 24. Alternatively, theadjustment of the pressure may be in the form of deploying a differentsize or characteristic device, which is self-expandable and applies adifferent force to the patient through the self-expandable wall. Theamount of satiety may be different for different patients. For example,a patient who is overweight may require a particular level of pressure,whereas a more obese, such as a morbidly obese, patient may require ahigher level of satiety. Likewise, a child or an adolescent may requiredifferent levels of pressure. The ability to obtain immediate feedbackon satiety strength allows the efficacy of the system to be establishedat deployment rather than monitoring the patient for weight loss andadjusting it after the patient has lost either too much or too littleweight.

Alternately, the amount of satiety can be gauged by where the patientfalls on the satiety continuum—that is whether they are hungry,satisfied, full or even nauseous. For a morbidly obese person, it may bedesirable to apply sufficient pressure so that the patient is nauseousand then optionally reduced slightly so that the patient just belowbeing nauseated or at a sub-nauseous level. This may be particularlyuseful when a remote control is being used in combination with anadjustable device where the patient may themselves adjust the level ofpressure to maintain their desired or a prescribed level of satiety.

Any of the bariatric devices 15-1015 may be used as part of amulti-disciplinary comprehensive program. This may include theadjustment of medications as the patient experiences weight loss. Forexample, for patients taking diabetic medications, less insulin may berequired as a patient loses weight. Also, blood pressure medications andother medications may be adjusted as the patient loses weight.

Because of the ability of the bariatric device 15-1015 to cause satiety,it is possible, in certain patients, that the patient will requirenutritional supplements, such as protein liquids, in order to ensureadequate nutritional needs, such as protein intake. Also, anti-nauseamedications may be given to the patient, especially at the beginning ofthe placement. This is because a bariatric device, according to theinvention, may cause nausea at the beginning of the placement.

In order to reduce the likelihood of food getting caught in the lumenand in order to minimize interference with natural peristalsis in theesophagus, the length of the lumen is generally kept below 9 cm. In mostembodiments, the length of the lumen is in the range of approximately 6cm to approximately 7 cm. Widened portions of the body, such as distalportions 17 c-1017 c, are not considered part of the lumen fordetermining the length of the lumen. The expandable wall, whetherself-expanding or balloon-expandable, should provide consistent pressureover as large an area as possible in order to induce adequate satiety,consistent with an effort to keep the lumen as short as possible.

Thus, it is seen that the present invention introduces a new category ofweight loss techniques: implied satiation. The invention advantageouslyutilizes stretch receptors, such as those located at the abdominalportion of the esophagus and/or esophageal-gastric junction and/or thecardiac portion of the stomach of the patient to cause satiety. Incontrast to gastric bypass surgery and adjustable gastric bands, thepresent invention does not require surgical intervention. In thatregard, the present invention provides a non-invasive or minimallyinvasive alternative. However, the invention may be utilized incombination with known restrictive and/or malabsorptive techniques, suchas gastric bypass surgery and adjustable gastric bands to further helpthe patient lose weight. Advantageously, the present invention may beapplied to patients who are contraindicated for surgery, such as thosewith mildly high obesity and for those at risk for surgery. Also, theinvention may be used to achieve sufficient weight loss in morbidlyobese patients to stabilize the patient for gastric bypass surgery.Moreover, the present invention may be properly sized for use withchildren and adolescence. Thus, the present invention provides anon-intrusive or minimally intrusive technique for addressing theincreasing epidemic of obesity in adolescents and children, as well asadults.

The present invention also comprehends an implied satietor that iscapable of exerting pressure at the patient's abdominal portion of theesophagus, esophageal-gastric junction and/or cardia, such as bysuitable dimensioning of a self-expanding wall or by a mechanism forexpanding the wall outwardly. Examples of such a mechanism may be abladder mechanism whereby the wall could exert varying pressures. Thepresent invention also has the capability of assisting in reducingesophageal leakage. This may further enhance the use of the invention incombination with other techniques, such as gastric bypass surgery,esophageal tumors, and the like. In addition to influencing theneurohormonal feedback mechanism present at the abdominal portion of theesophagus, the present invention is capable of resisting egress from thelumen of the satiety device. This provides additional benefit to certainpatients by resisting their ability to ingest food beyond satiety.Because the device may be inserted endoscopically with fluoroscopicassist, the device may be suitably and accurately positioned at thedesired location within the patient's esophagus, esophageal-gastricjunction and/or cardia and adjustments made to the satiety device asrequired. Moreover, the device may be subsequently removed from thepatient if indicated. The use of various fixation systems allow thedevice to be positioned at or near the abdominal portion of theesophagus, the esophageal-gastric junction and/or the cardia whileresisting distal migration of the device. Moreover, the use of suchfixation system may allow for the satiety device to be readily removedfrom the patient.

Evidence of the viability of the invention can be seen by its principlehaving been reduced to practice and found to cause weight loss inpatients. The patients, who ranged from non-obese to morbidly obese,lost weight, generally over a one or two week period during which thedevice was in place. The patients experienced some initial nausea. Theyreported satiety throughout placement of the device. When the device wasno longer present, the patients regained hunger.

Changes and modifications in the specifically described embodiments canbe carried out without departing from the principles of the invention,which is intended to be limited only by the scope of the appendedclaims, as interpreted according to the principles of patent lawincluding the doctrine of equivalents.

1. A bariatric device comprising: a body having a wall defining a lumen,said wall configured to generally conform to the shape and size of atleast one chosen from i) the abdominal portion of the esophagus and ii)the proximal cardiac portion of the stomach, said wall adapted to exerta force on the at least one chosen from i) the abdominal portion of theesophagus and ii) the proximal cardiac portion of the stomach therebyinfluencing a neurohormonal feedback mechanism to cause at least partialsatiety by augmenting fullness caused by food and simulating fullness inthe absence of food, and a fixation system to resist distal migration ofsaid body, said fixation system including at least a portion of saidwall adapted to promote ingrowth of tissue in said wall.
 2. Thebariatric device as claimed in claim 1 wherein said fixation systemincludes at least one opening in said wall to promote ingrowth oftissue.
 3. The bariatric device as claimed in claim 2 wherein said atleast one opening comprises a plurality of discrete openings.
 4. Thebariatric device as claimed in claim 2 wherein said at least one openingcomprises a lattice of openings.
 5. The bariatric device as claimed inclaim 1 wherein said at least one portion of said wall comprisessubstantially the entire said wall.
 6. The bariatric device as claimedin claim 1 wherein said at least a portion of said wall comprises alimited portion of said wall.
 7. The bariatric device as claimed inclaim 1 wherein said fixation system includes another fixation mechanismto resist distal migration of said body.
 8. The bariatric device asclaimed in claim 1 wherein said body is made at least in part from anabsorbable material.
 9. The bariatric device as claimed in claim 1wherein said lumen is substantially free of restriction.
 10. Thebariatric device as claimed in claim 1 wherein said wall is adapted toexert a force without the presence of food.
 11. A bariatric devicecomprising: a body having a wall defining a lumen, wherein said wallincludes a wall portion defining an esophageal member sized to conformto an abdominal portion of the esophagus, another wall portion defininga cardiac member sized to conform to a proximal cardiac portion of thestomach and a further wall portion extending between said esophagealmember and said cardiac member, wherein said esophageal member and saidcardiac member are adapted to exert a force on the abdominal portion ofthe esophagus and the proximal cardiac portion of the stomach therebyinfluencing a neurohormonal feedback mechanism to cause at least partialsatiety by augmenting fullness caused by food and simulating fullness inthe absence of food, wherein at least a portion of said wall is adaptedto promote ingrowth of tissue, wherein the ingrowth of tissue at said atleast a portion of said wall in reaction to the presence of said body inthe recipient fixes said body to the anatomy of the recipient to resistdistal migration.
 12. The bariatric device as claimed in claim 11wherein said at least a portion of said wall includes at least oneopening in said wall.
 13. The bariatric device as claimed in claim 12wherein said at least one opening comprises a plurality of discreteopenings.
 14. The bariatric device as claimed in claim 12 wherein saidat least one opening comprises a lattice of openings.
 15. The bariatricdevice as claimed in claim 11 wherein said portion of said wallcomprises substantially the entire said wall.
 16. The bariatric deviceas claimed in claim 11 wherein said portion of said wall comprises alimited portion of said wall.
 17. The bariatric device as claimed inclaim 11 including another fixation mechanism to resist distal migrationof said body.
 18. The bariatric device as claimed in claim 11 whereinsaid body is made at least in part from an absorbable material.
 19. Thebariatric device as claimed in claim 11 wherein said lumen issubstantially free of restriction.
 20. The bariatric device as claimedin claim 11 wherein said wall is adapted to exert a force without thepresence of food.
 21. A method of causing at least partial satietycomprising: positioning a body at least one chosen from i) an abdominalportion of the esophagus and ii) a proximal cardiac portion of thestomach, said body having a wall defining a lumen, said wall configuredto generally conform to the shape and size of the at least one chosenfrom i) the abdominal portion of the esophagus and ii) the proximalcardiac portion of the stomach; exerting force with the wall at the atleast one chosen from i) the abdominal portion of the esophagus and (ii)the proximal cardiac portion of the stomach thereby influencing aneurohormonal feedback mechanism of the patient to cause at leastpartial satiety by augmenting fullness caused by food and simulatingfullness in the absence of food; and fixing said body against distalmigration including promoting ingrowth of tissue at least a portion ofsaid wall.
 22. The method as claimed in claim 21 wherein said portion ofsaid wall includes at least one opening in said wall.
 23. The method asclaimed in claim 22 wherein said at least one opening comprises aplurality of discrete openings.
 24. The method as claimed in claim 22wherein said at least one opening comprises a lattice of openings. 25.The method as claimed in claim 21 wherein said portion of said wallcomprises substantially the entire said wall.
 26. The method as claimedin claim 21 wherein said portion of said wall comprises a limitedportion of said wall.
 27. The method as claimed in claim 21 wherein saidfixing said body includes using another fixation mechanism to resistdistal migration of said body.
 28. The method as claimed in claim 21wherein said promoting ingrowth of tissue provides relative permanenceof said body in the anatomy of the recipient.
 29. The method as claimedin claim 21 wherein said promoting ingrowth of tissue incorporates saidbody in the anatomy of the recipient.
 30. The method as claimed in claim21 wherein the ingrowth of tissue resists infection.
 31. The method asclaimed in claim 21 including removing said body from the recipient byremoving the ingrowth of tissue.